Many chronic disease conditions, such as hypertension, heart failure, kidney disease and liver disease, are associated with sodium retention and/or edema. By inhibiting sodium (Na) reabsorption at different sites in the nephron, conventional diuretics help regulate sodium and fluid homeostasis to relieve edema. Several different classes of small molecule diuretics are known, including loop diuretics, such as furosemide, bumetanide, and torasemide which act in the ascending loop of Henle; thiazide-related compounds including indapamide, hydrochlorothiazide and bendroflumethiazine which act in the distal tubule; and the potassium-sparing diuretics including amiloride and triamterene which act in the cortical collecting duct. See Plant, L., Clinical Medicine, 3, 517-519 (2003). Many patients with hypertension or congestive heart failure, however, are unresponsive to conventional diuretics. Thus, there is a need for new treatment strategies to control the blood pressure and fluid volume in such patients, and in other subjects.